Beth Sanden has completed marathons on all seven continents. And the North Pole. And Antarctica. But her role as a coach can be just as rewarding. In fact, she has convinced her spine surgeon to walk the Huntington Beach Doggy Dash Cause for Paws 5K with her on Saturday morning. Not only will Dr. Burak Ozgur, a neurosurgeon and director of the Hoag Spine Center, be out there on the course, but members of his office staff — Yulia Korol, Vernice Stern, Janneinne Le — are participating too. “She inspired our whole office to do it,” Ozgur said with a smile.The idea started when Sanden, who lives in San Clemente, came in for her six-month checkup following spinal surgery.